Heat sink

ABSTRACT

An exemplary heat sink includes a base plate and a fin unit including a plurality of fins arranged on the base plate. One of the base plate and fin unit includes a protruding member, and the other one of the base plate and the fin unit defines a groove corresponding to the protruding member. The protruding member is interferingly fitted in the groove thereby connecting the fin unit and the base plate together.

BACKGROUND

1. Technical Field

The disclosure generally relates to device cooling, and more particularly to a heat sink including a base plate and a fin unit interferingly fitted together.

2. Description of Related Art

Heat sinks are used to remove heat from heat-generating electronic components such as central processing units (CPUs) and others. Thereby, heat sinks keep electronic components within safe operating limits, and enable the electronic components to operate stably. A typical heat sink comprises a base contacting an electronic component and absorbing heat therefrom, and a plurality of parallel planar fins attached to the base by soldering. The fins dissipate the heat to the ambient environment.

When the above-described heat sink is manufactured, soldering flux needs to be added between the fins and the base when the fins are assembled to the base. Furthermore, when the fins and the base are made of different materials, a prior process of nickel-plating may be required before the fins and the base are soldered together. Such process materials and manufacturing procedures make the assembly of the fins and the base somewhat costly and complicated.

Another common kind of heat sink is the one-piece heat sink made of forged aluminum. However, the one-piece heat sink typically does not attain a very high heat dissipating effect. In particular, a short pitch between adjacent heat dissipating fins is desired, because a higher fin density provides a higher overall heat dissipating surface. However, due to technical difficulties inherent in the forging process, the desired level of fin density normally cannot be achieved economically.

What is desired, therefore, is a heat sink which can overcome the above described shortcomings

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric, assembled view of a heat sink according to a first exemplary embodiment of the present disclosure.

FIG. 2 is an isometric, exploded view of the heat sink of FIG. 1.

FIG. 3 is an isometric, exploded view of the heat sink of FIG. 1, shown from a different aspect.

FIG. 4 is an isometric, assembled view of a heat sink according to a second exemplary embodiment of the present disclosure.

FIG. 5 is an isometric, exploded view of the heat sink of FIG. 4.

FIG. 6 is an isometric, exploded view of the heat sink of FIG. 3, shown from a different aspect.

DETAILED DESCRIPTION

Reference will now be made to the figures to describe the present heat sink in detail.

Referring to FIG. 1, a heat sink 10 according to a first exemplary embodiment of the present disclosure includes a base plate 12 and a fin unit 14 arranged on the base plate 12.

Referring also to FIG. 2, the base plate 12 is rectangular, and includes a planar bottom surface 120 and a top surface 122. The bottom surface 120 is configured to contact a heat-generating component to absorb heat generated therefrom. A swallowtail-shaped protruding member 124 extends upwardly from a middle portion of the top surface 122. The protruding member 124 is made by an extrusion process, and has a substantially trapezoidal cross section. The protruding member 124 includes a rectangular top face 125 spaced from and parallel to the top surface 122 of the base plate 12, and two lateral faces 127 obliquely depending from two long sides of the top face 125 to connect the top surface 122 of the base plate 12. An arced chamfer 128 is formed between each of the lateral faces 127 and a corresponding long side of the top face 125. The protruding member 124 has a length equal to the base plate 12, and a width increasing gradually from the top surface 122 of the base plate 12 to the top face 125.

The fin unit 14 includes a plurality of fins 141 arranged on the top surface 122 of the base plate 12. Each of the fins 141 is a substantially rectangular thin metallic plate. The fins 141 are parallel to each other. Each of the fins 141 includes a substantially rectangular main body 140, and a flange 142 extending from an upper edge of the main body 140. A cutout 144 corresponding to the protruding member 124 is defined in a middle of a lower end of the main body 140. Referring also to FIG. 3, the cutout 144 is formed by extrusion tapping, such that a hem 145 extending along a periphery of the cutout 144 is accordingly formed. A main central portion of the hem 145 is parallel to the flange 142, and a length of the main central portion of the hem 145 is less than, but similar to, a length of the flange 142. The cutout 144 has a shape which is the same as the shape of the cross section of the protruding member 124. A size of the cutout 144 is substantially the same as a size of the cross section of the protruding member 124.

When the heat sink 10 is assembled, the fins 141 are individually installed onto the base plate 12. Each fin 141 is firstly placed at one side of the base plate 12, with the cutout 144 aligned with the protruding member 124. Then the fin 141 is horizontally mounted onto the base plate 12 with the protruding member 124 being received in the cutout 144. The protruding member 124 interferingly fits in the cutout 144. The hem 145 abuts the top face 125 and lateral faces 127 of the protruding member 124, to provide a large contact interface between the fin 141 and the base plate 12. Each of the fins 141 is horizontally moveable along the protruding member 124, such that positions of the fins 141 on the base plate 12 can be adjusted as needed during assembly. After all of the fins 141 are assembled onto the base plate 12, the flanges 142 of each two neighboring fins 141 contact each other, to cooperatively form a planar top surface 146 at an upper side of the fin unit 14. The hems 145 of the each two neighboring fins 141 contact each other to cooperatively define a groove 147 at a lower end of the fin unit 14. The groove 147 matches the protruding member 124.

In the present heat sink, soldering flux and nickel plating are not required during assembly of the fins 141 and the base plate 12. This greatly reduces a manufacturing cost of the heat sink 10, and allows assembly of the fins 141 and the base plate 12 to be simple and convenient.

FIGS. 4 and 5 show a heat sink 10 a according to a second exemplary embodiment of the present disclosure. The heat sink 10 a differs from the heat sink 10 of the first embodiment only in that a protruding member 124 a is formed at a lower end of a fin unit 14 a, and a groove 144 a is defined at a top surface 122 a of a base plate 12 a. The groove 144 a has the same shape as that of the protruding member 144 of the first embodiment. The fin unit 14 a includes a plurality of fins 141 a arranged on the top surface 122 a of the base plate 12 a. Referring also to FIG. 6, each of the fins 141 a includes a protrusion 126 a depending from a lower edge of the main body 140, and a hem 127 a extending along a periphery of the protrusion 126 a and being oriented perpendicular to the main body 140. The protrusion 126 a has the same shape as that of the cutout 144 of the first embodiment. The protrusion 126 a has the same shape as a cross section defined by the groove 144 a of the base plate 12 a, and has substantially the same size as the cross section of the groove 144 a. A main central portion of the hem 127 a is parallel to a flange 142 of the fin 141 a, and a length of the main central portion of the hem 127 a is less than, but similar to, a length of the flange 142.

When the heat sink 10 a is assembled, the fins 141 a are individually assembled onto the base plate 12 a one by one. Each fin 141 a is firstly placed at one side of the base plate 12 a with the protrusion 126 a aligned with the groove 144 a. Then the fin 141 a is horizontally mounted onto the base plate 12 a, with the protrusion 126 a being received in the groove 144 a. The protrusion 126 a interferingly fits in the groove 144 a. The hem 127 a abuts an inner surface of the base plate 12 a in the groove 144 a. After all of the fins 141 a are assembled onto the base plate 12 a, the hems 127 a of each two neighboring fins 141 a contact each other to cooperatively form an outer surface of the protruding member 124 a. The protrusions 126 a cooperatively form the protruding member 124 a at the lower end of the fin unit 14 a. The protruding member 124 a matches the groove 144 a of the base plate 12 a.

It is to be understood, however, that even though numerous characteristics and advantages of the embodiments have been set forth in the foregoing description, together with details of the structures and functions of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the disclosure to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. 

1. A heat sink, comprising: a base plate; and a fin unit comprising a plurality of fins arranged on the base plate; wherein one of the base plate and fin unit comprises a protruding member, the other one of the base plate and the fin unit defines a groove corresponding to the protruding member, and the protruding member is interferingly fitted in the groove thereby connecting the fin unit and the base plate together.
 2. The heat sink of claim 1, wherein the protruding member extends upwardly from one side surface of the base plate, each of the fins defines a cutout thereof, the cutouts of the fins cooperatively forming the groove.
 3. The heat sink of claim 2, wherein the protruding member has a substantially trapezoid cross section.
 4. The heat sink of claim 2, wherein the protruding member comprises a top face spaced from the side surface of the base plate and two lateral faces obliquely depending from the top face to connect the side surface of the base plate, the protruding member having a width increasing gradually from the side surface of base plate to the top face.
 5. The heat sink of claim 4, wherein an arced chamfer is formed between each of the lateral faces and the top face.
 6. The heat sink of claim 2, wherein each of the fins comprises a main body and a flange extending outward from an upper edge of the main body, the cutout being defined in a lower end of the main body, a hem extending along a periphery of the cutout angling outward from the main body, the hem being oriented along the same axis as the flange.
 7. The heat sink of claim 6, wherein a main central portion of the hem is parallel to the flange, and a length of the main central portion of the hem is less than a length of the flange.
 8. The heat sink of claim 6, wherein the hems of the fins contact an outer surface of the protruding member.
 9. The heat sink of claim 1, wherein the groove is defined in one side surface of the base plate, each of the fins comprising a protrusion thereof, the protrusions of the fins cooperatively forming the protruding member.
 10. The heat sink of claim 9, wherein a cross section defined by the groove of the base plate is substantially trapezoid shaped.
 11. The heat sink of claim 9, wherein each of the fins comprises a main body and a flange extending outward from an upper edge of the main body, the protrusion depending from a lower edge of the main body, a hem extending along a periphery of the protrusion angling outward from the main body, the hem being oriented along the same axis as the flange.
 12. The heat sink of claim 11, wherein a main central portion of the hem is parallel to the flange, and a length of the main central portion of the hem is less than a length of the flange.
 13. The heat sink of claim 11, wherein the hems of the fins abut an inner surface of the base plate in the groove.
 14. A heat sink, comprising: a base plate comprising a protruding member extending upward from a top surface thereof; and a fin unit comprising a plurality of fins arranged on the base plate, each of the fins defining a cutout in a bottom thereof, each of the cutouts having the same shape as a cross section of the protruding member of the base plate and a size substantially the same as that of the cross section of the protruding member; wherein the fins are attached to the base plate with the protruding member interference fitted in the cutouts such that the fin unit and the base plate are connected together.
 15. The heat sink of claim 14, wherein the protruding member comprises a top face spaced from the top surface of the base plate and two lateral faces obliquely depending from the top face to connect the side surface of the base plate, the protruding member having a width increasing gradually from the top surface of base plate to the top face.
 16. The heat sink of claim 14, wherein each of the fins comprises a main body and a flange extending outward from an upper edge of the main body, the cutout being defined in a lower end of the main body, a hem extending along a periphery of the cutout angling outward from the main body, the hem being oriented along the same axis as the flange.
 17. The heat sink of claim 16, wherein the cutouts of the fins cooperatively form a groove corresponding to the protruding member of the base plate.
 18. A heat sink, comprising: a base plate defining a groove recessed from a top surface thereof; and a fin unit comprising a plurality of fins arranged on the base plate, each of the fins comprising a protrusion, the protrusion having the same shape as a cross section defined by the groove of the base plate and a size substantially the same as that of the cross section of the groove; wherein the fins are attached to the base plate with the protrusions interference fitted in the groove such that the fin unit and the base plate are connected together.
 19. The heat sink of claim 18, wherein each of the fins comprises a main body and a flange extending outward from an upper edge of the main body, the protrusion depending from a lower edge of the main body, a hem extending along a periphery of the protrusion angling outward from the main body, the hem being oriented along the same axis as the flange.
 20. The heat sink of claim 18, wherein the protrusions of the fins cooperatively form a protruding member corresponding to the groove of the base plate. 